The 1,389 directors of FTSE 100 companies received pay packages totalling £1,013,076,577 last year - enough to pay for 15 new hospitals or 50,000 new nurses. It is the first time that the £1bn barrier has been breached.

The lion's share - £929m - was earned by 527 executive directors, and nearly £700m of that was performance-related annual bonuses and share awards. Basic salaries for directors rose only 5% to £230m but still outstripped average earnings across the workforce, which increased by 3.3% in the year to the end of June.

Sir Ronald Cohen, founder of the private equity firm Apax Partners and an adviser to the prime minister, Gordon Brown, recently said the growing rich-poor divide could prompt riots in the streets.

However, companies argue that they must pay globally competitive salaries to attract the best talent and stop a brain drain into private equity.

The best-paid boardrooms were at Barclays and Reckitt Benckiser, where the two best-paid directors in the Guardian/ RTF survey dominated payouts.

At Barclays, for instance, Bob Diamond's £23m accounted for 40% of total boardroom rewards, while at Reckitt Benckiser the chief executive, Bart Becht, is paid nearly 80% of the household cleaning group's executive wage bill.

Other companies with boardroom payouts in excess of £20m included the mining group BHP Billiton, the supermarket chain Tesco and the oil exploration group Cairn Energy. The blue-chip company whose directors have the most modest payouts is Antofagasta, a family-dominated Chilean copper mining company which is listed on the London Stock Exchange. Directors drew a total of just £1.7m. Other bargain basement boards include Associated British Foods - the company behind Kingsmill bread and the Primark discount fashion chain - and Kelda, the owner of Yorkshire Water, where both boards of directors drew less than £2m.

Standard Chartered Bank's Mervyn Davies, who last year moved up from chief executive to non-executive chairman, was the best-paid chairman, with a salary package of £4m. HSBC's Stephen Green, who was also chief executive before being elevated to the chairman's office, received £3.8m. The average non-executive chairman earned £311,000.

The Guardian survey also reveals the best and worst-paid employees working for blue-chip companies. The top earners are almost all employed by financial services companies and are led by those working for 3i, a quoted private equity group. Their average salary last year broke through £200,000, boosted by spectacular investment returns on deals such as NCP car parks. Other financial sector workers to feature among the FTSE 100's best paid include those employed by the money broker ICAP, the hedge fund group Man and the fund manager Schroders.

The financial companies also have the flattest structures - their bosses are valued at less of a premium to those on the shopfloor. 3i's chief executive Philip Yea, for instance, is paid just 11 times the average company salary.

The highly unionised British Airways has also maintained a relatively narrow gap between the salary paid to the chief executive, Willie Walsh, and the airline's workforce. Mr Walsh is paid just 13 times the average BA salary of £49,000.

The other end of the wage spectrum is dominated by miners, retailers and pubs. The average salary at Vedanta, an Indian mining company, is just £5,148. But UK-based companies including Tesco, Next, Punch Taverns, Sainsbury's and Wm Morrison are also at the bottom of the table, largely because of part-time workers.

The survey also highlights those directors who sit in the boardrooms of more than one FTSE 100 company. A total of 16 directors are on the boards of three or more. The busiest is John Buchanan, a former Shell executive, who now divides his time between Vodafone, Smith & Nephew, BHP Billiton and AstraZeneca.

The Guardian/RTF survey does not include contributions to pension schemes. However, data from company annual reports show that 17 executives have accumulated pension pots big enough to provide annual pensions of £500,000 or more. They include Tesco's boss, Sir Terry Leahy; Paul Walsh of Diageo and Paul Dacre of the Daily Mail but are led by the recently retired Lord Browne, who has built a pension fund of nearly £20m.

Lord Browne will not have to live just on the £1m a year that his pot will give him - he recently joined a new private equity group, Riverstone, as managing partner.

How it works

The data for the Guardian pay survey have been derived from the latest annual reports of the 106 companies that were members of the FTSE 100 from the end of June last year to the end of June this year (with the exception of Carnival plc, whose pay data was not included). Directors' pay was calculated by adding basic pay, the value of benefits (such as cars, health and life insurance) cash and deferred bonuses together with gains from long term incentive plans. The data cover 1,389 FTSE 100 directors who received payments from their employers in the last financial year (typically 2006). Those directors who had left or joined their boards during the course of the year were excluded. This left 1,174 directors who were employed throughout the year. The Guardian pay survey data was researched by the Reward Technology Forum.